20565972 has 36 divisors (see below), whose sum is σ = 59413536. Its totient is φ = 5875920.

The previous prime is 20565913. The next prime is 20565977. The reversal of 20565972 is 27956502.

20565972 is a `hidden beast` number, since 2 + 0 + 565 + 97 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20565977) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 40554 + ... + 41057.

It is an arithmetic number, because the mean of its divisors is an integer number (1650376).

Almost surely, 2^20565972 is an apocalyptic number.

It is an amenable number.

20565972 is an abundant number, since it is smaller than the sum of its proper divisors (38847564).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20565972 is a wasteful number, since it uses less digits than its factorization.

20565972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81628 (or 81623 counting only the distinct ones).

The product of its (nonzero) digits is 37800, while the sum is 36.

The square root of 20565972 is about 4534.9721057577. The cubic root of 20565972 is about 273.9784556914.

The spelling of 20565972 in words is "twenty million, five hundred sixty-five thousand, nine hundred seventy-two".